Harry entered into the room filled with flashing, swirling mists contained in enchanted jars. He had long awaited entrance into this room, where the memories of deceased witches and wizards were kept.

It hadn't been that hard, really, to gain access to this room. He had been teaching Defense Against the Dark Arts at Hogwarts since he turned 40, and no, after 5 years, he felt that he needed to see this one memory.

He passed the isles, finally turning down the one marked Duade-Haabs.

As he walked down the isle, he was stunned by how many memories had been gathered from pensieve's over the years. He supposed that they must have been collecting these for centuries, and was saddened by the fact that he was only granted access to one memory.

'I might want to come back here someday,' he thought to himself as he came upon the shelf containing the memories of A.P.W.B. Dumbledore.

His first reaction was that of awe. It wasn't just a single shelf, but shelf upon shelf, stacked with jars from the floor to the ceiling (the highest of which surely required a ladder, or at least a steady levitation charm, to get down). He then noticed that there weren't one, nor two, but 13 shelves full of Dumbledore's memories.

Harry thought briefly that perhaps, in his last year on earth, knowing his end was coming, he might have attempted to put more and more of his memories into his pensieve for posterities sake.

He was able to tell that they were ordered from his earliest memories to his latest, so he made his way towards the middle shelves. The memory he wanted was from 1945.

As he walked he glanced at the jars, labeled with date, time and whom or what the memory pertained to. He was stopped cold in his tracks when he saw the one labeled APWBD; ASD; AMD; GG : August 23rd, 1899: 4:45pm. He knew that this was probably Dumbledore's most personal memory, and could not believe it had been included.

Harry reached for the jar even though he knew he shouldn't, this was not the memory he was supposed to collect, but he could not help his curiosity.

As his hand was about to close around the jar, he felt an incredibly sharp pain run from his finger tips up to his shoulder. Harry quickly recoiled his wand arm from the jar, crying out in pain.

He was surprised both at how intense the pain had been (it rivaled the Cruciatous Curse there), and at how quickly the pain had subsided upon pulling his hand back. He realized then that there must be security features on these memories so only those who are authorized could remove them. He moved on.

He finally found the memory that he had been looking for. It was clearly labeled APWBD; GG : May 7, 1945 : 2:13pm.

Harry reached for the memory, ready to pull his hand back again should it be necessary, though he did not expect the pain again.

As his fingers closed around the jar, he felt it grow very warm, almost unbearably hot, then go back down to a normal temperature.

Satisfied that he was not going to be cursed for this memory, Harry lifted the jar, and began walking back to the viewing room.

HPHPHPHPHPHPHPHP

Harry removed the lid from the jar, standing around the stone basin of the pensieve. The Auror who was escorting him, as well as the Unspeakable who was working the desk of the Memories Department, a sub department of the Department of Mysteries, left the room so Harry could see the memory alone, at his leisure.

Harry could clearly remember the duel between Dumbledore and Voldemort from when he was just a teenager. It been, and still was to this day, the most awesome display of sheer magical power and abilities he had ever witnessed. He had collected that memory into a pensieve not long after Voldemorts defeat, and had shared it with only a few whom he was closest to (including his wife, Ginny, and his children) until he became a teacher at Hogwarts.

Since then, he had saved the memory for his 7th year NEWT level course work. He had let it slip in every first year class that the memory was available to be viewed by 7th years for private study after the showing for the entire class half way through the year. He had hoped that that memory, coupled with him being the infamous "Boy-Who-Lived", would be enough to convince his students to take his subject seriously, and make it to the NEWT level courses. He did not want to risk another Dark Lord coming around and having so few people prepared to defend themselves ever again.

Harry was very anxious to finally be seeing this memory. There were two reasons that Harry really wanted to see this memory. The first was simply that it had always been said by those few witnesses that this duel was unrivaled in history in its intensity and sophistication. He had long wondered what that would look like, and if it would indeed rival the power he had seen between Dumbledore and Voldemort. He had hoped that, if it was indeed as spectacular of a duel as everyone claimed it to have been, he could gain access to it as well for his NEWT level classes.

The second reason was to answer a question that he had been asking for years and years. 'How did Dumbledore defeat Grindlewald if he held the Ender Wand?'

Harry had seen another wizard, Draco Malfoy, disarm Dumbledore in his 6th year, just before Dumbledore died. That had been a fluke, a coincidence of timing and fate. It had not been done in a proper duel (though Harry figured Dumbledore then could take Malfoy now, at his prime, with his wand arm tied behind his back using Ron's old broken wand from their 2nd year), and he was curious to see how it had panned out in 1945.

Harry emptied the contents of the jar into the stone basin, and saw them swirl. He took a breath, leaned his head forward, and felt himself fall forward into the basin.

HPHPHPHPHPHPHPHP

Harry was shocked to see he was in a white room, and Albus Dumbledore was standing right in front of him, looking at him squarely in the face.

"Hello, Harry, I was wondering if I would meet you here," the memory of Dumbledore said.

"What?" Harry cried out in shock. "How are you talking to me, how can you pos-"

"It's ok, Harry. I can't really see you, and I can't really communicate with you. In my will, I left my memories to the ministry with very few restrictions. This is one of them that I had restricted. You see, I didn't want the world to know that I was once close to Gellert. That is one of my secrets that I have never disclosed, and it is quite possible that this is the first you have ever heard of it.

"With that in mind, I restricted this memory to be only accessible by 3 people, yourself being one of them. I also placed an enchantment, using memories I have of yourself, so that my memory would recognize your presence, and play this message for you.

"Once you have viewed it, you will have the ability to share it, in its entirety, or in part, with anyone you desire. I only ask that you do so with my request in mind, that when and if you do share it, you share only the parts that are relevant, and not anything that you may find personal. I trust you to be able to make the distinction.

"I also want to say that I am sorry I could not fully confide in you my plans with Severus when I died. I hope you have forgiven me."

And the room, with Dumbledore, faded away.

HPHPHPHPHPHPHPHP

Harry was shocked at the scene that materialized before him. It must have been Berlin during the second Great War of the muggle world. Harry knew that Grindelwald had somehow been involved in that, and he had only the vaguest memories of the events that led to this kind of destruction from when he had been in school as a child, before he had even known he was a wizard.

He was in a street, and noticed Dumbledore, though much, much younger than the Dumbledore he remembered, slowly walking towards him, a look of disgust, anger, and resolve on his face.

Dumbledore had to be careful with his footsteps as the road was strewn with rubble. The buildings on either side had been ripped to shreds, and Harry wondered if it had been caused by one of those famous muggle bombing raids, or by wizards dueling. Either way, it was a sight to behold, though a very morbid one.

Dumbledore turned a corner down another road before he reached Harry, and Harry ran to see where he was going. Dumbledore though, had stopped cold when turned.

There, before him, was a man he had only seen through the eyes of Voldemort. He had seen this man when he had seen the memory where Grindelwald stole the wand from Gregorovitch, and then, later, when he had tortured, and subsequently murdered him in prison. But he wasn't alone.

On the ground, writhing in pain, was a muggle dressed in a military outfit. He could not tell the nationality, but the man cried out in English as he begged for mercy.

Harry turned and saw Dumbledore slowly raise his wand, and a flash of light emitted from his wand, striking the Ender Wand, and knocking it out of Grindelwald's grasp.

The muggle sighed in relief and slipped into unconsciousness before the wand hit the ground. Grindelwald did not even look up to see who had disarmed him. It was obvious he knew. He simply reached down for his wand as he started speaking.

"Finally, someone worth my time," he said under his breath, though both he and the younger version of Dumbledore could clearly hear.

"Gellert, this must end. You've gone too far, and this has gone on for far too long. I'm so disappointed to see what you have become," Albus said, and Harry was shocked to realize that the man was visibly shaken, almost holding back tears.

Grindelwald stood up straight, his wand in hand. Harry now had the question answered. From what little he understood of wand lore, it was possible, and given the eventual outcome of the duel, likely that the wand had just transferred allegiance to Dumbledore when Grindelwald was disarmed. With that out of his mind, he knew he would be able to focus more on the duel that was about to come.

"Albus, my good friend, I must say it is wonderful to see you again. It's only been, how long? Forty-five years, is that right? How have you been, my dear?" Gellert asked in a mocking tone.

Harry could not believe what he was hearing. Did Grindelwald just called Dumbledore my dear?

"Gellert, our relationship that summer so long ago ended as abruptly as it started, and I'm not here to discuss it. You are to return with me to the Joint Ministry Session of Greater Europe in Geneva. You will be placed on trial for murder, extortion, torture, and countless other crimes that you have committed. You will then be sentenced, and I only hope for your sake that you are executed so you do not have to ever come to terms with all that you have done."

Harry noted that, while when he had dueled Voldemort, Dumbledore's tone had been casual, frighteningly so, his voice was filled with rage and sadness when he spoke to Gellert. Harry was starting to wonder if there had been more to their "friendship" than most people realized.

"Albus, do not make me kill you. I have never enjoyed killing a single person before, rather you believe me or not, but I would truly mourn having to kill you. I was so hoping you would continue your rather loud absence from this war. What happened? Did you finally get pressured into it by the voices of the weak? "

"This conversation is over, Gellert, either come with me now peacefully, or I will bring you in using whatever method I must." Dumbledore's voice was ice cold.

"So be it, my good friend."

Harry noticed, before it began, that there was a small crowd starting to form. He could recognize Grindelwald's followers by the plain, black robes with white trim they wore, and he only assumed the others were with Dumbledore. Though they were there, neither side seemed interested in fighting, they were watching as intently as Harry was.

The first jet of light came from Grindelwald, and it was deathly green, without a doubt the killing curse. Dumbledore disappeared as he turned on the spot, and appeared behind Grindelwald.

Grindelwald was prepared for it, though, and with a quick flick of his wand, a huge piece of concrete from the rubble of a collapsed building flew at Dumbledore. It was blasted into a million pieces before it came close, and Dumbledore made the pieces fly towards Grindelwald.

Grindelwald then did something Harry had never seen before, he turned into what appeared to be a white mist, something like fog, and the pieces of rubble passed right through him. He then materialized and sent another killing curse at Dumbledore.

Dumbledore was apparently surprised to see what Grindelwald had just done as well, for he just barely managed to dive to the side, at the same time moving his wand in a circular motion, then pointing it directly at Grindelwald again.

Harry saw the pieces of rubble that had just passed through Grindelwald transfigure into a swarm of hornets, and immediately began to attack Grindelwald. There was a loud bang, and a bright flash of light, and the hornets fell to the ground burning.

Dumbledore had not wasted any time, however. He was already on his feet, and three spells were heading towards Grindelwald so close together they almost appeared to be the same spell. Harry only recognized the bright red of what had to be an advanced stunner, concusso. He was one of the few people he knew capable of casting that spell, as it was quite draining, though unlike stupefy, it could not be blocked, and was not reversible by any means other than a special potion.

Grindelwald disapperated and appeared in mid-air above Dumbledore. Harry cried out, temporarily forgetting they could not hear him. Grindelwald appeared to hover above Dumbledore for a split second, then fell down towards him, casting spell after spell, none of which Harry recognized.

Dumbledore dove to the side right before Grindelwald landed, and with a slashing motion of his wand, the spot where he had been standing a moment before opened up into an endless deep hole. This appeared to be trying to suck Grindelwald in, as he had to fight against it to not enter. Grindelwald barely managed to levitate himself back up before falling into the hole.

With a crack, the hole was gone. Dumbledore was once again on his feet, and as Grindelwald was still in mid-air, waved his wand in that similar lasso motion he had seen him use to pull Death Eaters back as they ran in the Ministry battle so long ago.

Grindelwald was pulled off of his course and into a the side of a building that had not yet been completely destroyed, but before he made impact he managed to transfigure the side of the building into a soft mattress that he rebounded off of without any pain.

He turned in mid-air, and as he landed, sent what could only be described as a wall of fire 7 feet high and 15 feet across towards Dumbledore.

Dumbledore turned, disapperated, and reappeared 50 feet from Grindelwald. The cries from those who had been hit from the wall of fire filled the sky, they appeared to have been Grindelwald's own followers. Harry noticed that Dumbledore's robes were slightly singed, as were his hair and beard. That had been a very close call.

There was a low rumbling as Dumbledore raised both of his hands above his head. A hundred pieces of rubble started to circle around Grindelwald, slowly moving in closer.

Grindelwald tried to turn in place to disapperate, but was obviously held in place by the spell, unable to escape it.

As the pieces of rubble gathered speed and began to close around him, he cast a protective charm Harry had never seen. It was as though a bubble of pure energy surrounded him, and the rubble, mostly concrete, bounced off of it.

Harry could tell by the look on Dumbledore's face he had not expected that. He appeared to be getting weary and tired from the duel already, but the protective charm Grindelwald had cast had apparently drained him some as well, as they both paused to catch their breath before continuing.

The next five minutes were much more like the duels Harry had fought in the past himself, an exchanging of spells with little use of transfiguration, and only once had Dumbledore had to apperate to avoid a killing curse. It appeared they had been in fact drained in their initial exchange and were biding their time before delving back into the more advanced spells.

Just as Harry had started to wonder when it would change back, Dumbledore disapperated and appeared only a few feet from Grindelwald.

He closed the distance until he was only 2 feet from Grindelwald, and they began to exchange rapid spells at close range faster than Harry had ever seen anyone cast before. It looked more like a dance than a duel, and each time their wands moved, there was a flash of light. It appeared that Dumbledore was not giving Grindelwald time to cast a killing curse, as there was no way he would have been able to avoid it.

Grindelwald disappeared, then appeared again some 20 feet to Dumbledore's left.

He slashed his wand through the air, and a bolt of lightning split the sky with a loud crack of thunder. Harry saw that it had almost hit Dumbledore, and would have had Dumbledore not stuck his wand into the air, apparently absorbing the lightning into it. He pointed his wand at Grindelwald, and the lightning erupted out of the wand, intensified by Dumbledore.

The lightning struck the ground at Grindelwald's feet, and flew him backwards. He landed with a heavy thud.

Dumbledore cautiously moved forward, aware that Grindelwald might very well be trying to lure him in closer.

Indeed that is what had happened. As Dumbledore got within 10 feet, Grindelwald unleashed yet another killing curse.

Dumbledore dove aside, slashing his wand across his body pointed towards Grindelwald.

Apparently, this worked. Caught off guard, Grindelwald lost his wand while trying to parry what Harry could only guess was some form of advanced strike, shock or bludgeoning hex.

Dumbledore then sent another cuncusso towards Grindelwald. It hit him squarely in the chest and he collapsed.

Harry let out a small sigh, and watched as Albus Dumbledore picked up the Elder Wand and pocketed it.

A/N: I feel like my version of this duel is missing something, however, I wanted to put some of my ideas into writing. You may notice the date of this duel is the day before VE day in WWII, alluding to the idea that Grindelwald may have had more to do with the muggle WWII than is originally put on in the books. Other than that, I'd love to have some reviews as this is my first attempt at fan fiction. I hope you enjoyed it.